Adhesion problems and warping
I own a Hephestos 2 for over a year now and although I was pretty happy with it I very much wanted to upgrade the 3D printer with a heated bed. The reason for that was not so much the desire to use other material like ABS but I was hoping for better adhesion. Adhesion problems in the past led to warping and misprints. To counter this I used BuildTak en Pritt. This helped most of the time but it also led to a new problem. It was very hard to remove the model from the printbed. With the help of a vise to clamp the printbed and a special knife I was able to do it but it was far from ideal (to say the least).
A heated bed is the obvious solution to this problem. Warping is mainly caused by uneven cooling and therefore shrinking of the different areas of the print. The printbed counters this effect by keeping the whole printbed warm and thus warming the print evenly over it’s surface.